/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com *//**   @file gcm_memory.c   GCM implementation, process a packet, by Tom St Denis*/#include "tomcrypt.h"#ifdef GCM_MODE/**  Process an entire GCM packet in one call.  @param cipher            Index of cipher to use  @param key               The secret key  @param keylen            The length of the secret key  @param IV                The initial vector   @param IVlen             The length of the initial vector  @param adata             The additional authentication data (header)  @param adatalen          The length of the adata  @param pt                The plaintext  @param ptlen             The length of the plaintext (ciphertext length is the same)  @param ct                The ciphertext  @param tag               [out] The MAC tag  @param taglen            [in/out] The MAC tag length  @param direction         Encrypt or Decrypt mode (GCM_ENCRYPT or GCM_DECRYPT)  @return CRYPT_OK on success */int gcm_memory(      int           cipher,               const unsigned char *key,    unsigned long keylen,               const unsigned char *IV,     unsigned long IVlen,               const unsigned char *adata,  unsigned long adatalen,                     unsigned char *pt,     unsigned long ptlen,                     unsigned char *ct,                      unsigned char *tag,    unsigned long *taglen,                               int direction){    void      *orig;    gcm_state *gcm;    int        err;    if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {       return err;    }     if (cipher_descriptor[cipher].accel_gcm_memory != NULL) {       return          cipher_descriptor[cipher].accel_gcm_memory                                          (key,   keylen,                                           IV,    IVlen,                                           adata, adatalen,                                           pt,    ptlen,                                           ct,                                           tag,   taglen,                                           direction);    }#ifndef GCM_TABLES_SSE2    orig = gcm = XMALLOC(sizeof(*gcm));#else    orig = gcm = XMALLOC(sizeof(*gcm) + 16);#endif    if (gcm == NULL) {        return CRYPT_MEM;    }   /* Force GCM to be on a multiple of 16 so we can use 128-bit aligned operations    * note that we only modify gcm and keep orig intact.  This code is not portable    * but again it's only for SSE2 anyways, so who cares?    */#ifdef GCM_TABLES_SSE2   if ((unsigned long)gcm & 15) {      gcm = (gcm_state *)((unsigned long)gcm + (16 - ((unsigned long)gcm & 15)));   }#endif    if ((err = gcm_init(gcm, cipher, key, keylen)) != CRYPT_OK) {       goto LTC_ERR;    }    if ((err = gcm_add_iv(gcm, IV, IVlen)) != CRYPT_OK) {       goto LTC_ERR;    }    if ((err = gcm_add_aad(gcm, adata, adatalen)) != CRYPT_OK) {       goto LTC_ERR;    }    if ((err = gcm_process(gcm, pt, ptlen, ct, direction)) != CRYPT_OK) {       goto LTC_ERR;    }    err = gcm_done(gcm, tag, taglen);LTC_ERR:    XFREE(orig);    return err;}#endif/* $Source: /cvs/libtom/libtomcrypt/src/encauth/gcm/gcm_memory.c,v $ *//* $Revision: 1.23 $ *//* $Date: 2006/09/07 10:00:57 $ */